67-56-1 Usage
Uses
Used in Chemical Manufacture:
Methanol is used as a main feedstock for the production of formaldehyde and its derivatives, hydrocarbon chains, aromatic systems, methyl tert-butyl ether, dimethyl terephthalic acid, methyl methacrylate, and acrylic acid methyl ester.
Used in Plastics Industry:
Methanol serves as a main feedstock in the production of polymers.
Used in Farm Chemical:
It is used as a main feedstock for the production of insecticides and acaricides.
Used in Pharmaceuticals:
Methanol is a main feedstock in the production of sulfonamides, amycin, and other pharmaceuticals.
Used in Fuel for Vehicles:
Methanol is used as pure methanol fuel, which does not produce an opaque cloud of smoke in the event of an accident.
Used in Methanol Gasoline:
It is blended directly into gasoline to produce a high-octane, efficient fuel with lower emissions than conventional gasoline.
Used in Chemical Analysis:
Methanol is used as an analysis agent for the determination of boron and trace moisture in alcohols, saturated hydrocarbons, benzene, chloroform, and pyridine.
Used in Others:
Methanol is used as a separation reagent for the separation of calcium sulfate and magnesium sulfate, and strontium bromide and barium bromide. It also serves as an effective component as an anti-freezing agent.
Methanol is also used as a solvent for lacquers, paints, varnishes, cements, inks, dyes, plastics, and various industrial coatings. It is used in duplicating fluid, paint removers, and as a cleaning agent. Additionally, it is used as a gasoline additive, in antifreeze preparations, and in canned heating preparations of jellied alcohol. Methanol has numerous applications in various industries, including as a fuel additive, extractant for animal and vegetable oils, to denature ethanol, and as a softening agent for pyroxylin plastics. It is also used as a solvent and solvent adjuvant for polymers and in the manufacture of cholesterol, streptomycin, vitamins, hormones, and other pharmaceuticals. Furthermore, methanol is used in high purity grade for ICP-MS detection and as a possible alternative to diesel fuel.
Methanol poisoning and First Aid Measures
Pathogenesis
First, methanol has a cumulative effect and is oxidized in the body into more toxic formaldehyde and formic acid. Methanol and its oxides directly damage the tissues, causing cerebral edema, meningeal hemorrhage, optic nerve and retinal atrophy, pulmonary congestion and edema, and hepatic and renal turbid swelling.
Second, methanol and its oxides cause blood circulation disorder, coenzyme system obstacles in vivo, resulting in lack of oxygen supply to the brain cortical cells, metabolic disorders, and related neurological and psychiatric symptoms.
Third, methanol oxidation products combine with the iron in the cytochrome oxidase, which inhibits the intracellular oxidation process thus causing metabolic disorders, acidosis along with organic acid accumulation in the body, and nerve cells impair.
Treatment
Keep away from the methanol dispersion area, excrete methanol from the body.
Antidote: Ethanol is an antidote to methanol poisoning. Ethanol can prevent methanol’s oxidation and promote its emission. Prepare 5% ethanol solution using 10% glucose solution, and drip slowly intravenously.
Maintain electrolyte balance: maintain respiratory and circulatory function, provide with a large number of Vitamin B.
Treatment of acidosis: Administrate timely sodium bicarbonate solution or sodium lactate solution based on blood gas analysis, carbon dioxide binding force measurement and clinical performance.
Prevent cerebral edemas actively, reduce intracranial pressure, improve fundus blood circulation, and prevent optic neuropathy if needed.
Inject intravenously cytochrome C, polar fluid to restore cytochrome oxidase function.
Control mental state by applying diazepam, perphenazine and the like.
Symptoms and treatments:
▼▲
Acute pain
morphine, pethidine
Convulsions
phenobarbital, amimystrine, diazepam
Coma
caffeine sodium benzoate
Respiratory failure
nikethamide, theophylline
Reactivities of Methanol
Methanol is the simplest aliphatic alcohol. It contains only one carbon atom. Unlike higher alcohols, it cannot form an olefin through dehydration. However, it can undergo other typical reactions of aliphatic alcohols involving cleavage of a C-H bond or O-H bond and displacement of the -OH group. Table 1 summarizes the reactions of methanol, which are classified in terms of their mechanisms. Examples of the reactions and products are given.
Homolytic dissociation energies of the C-O and O-H bonds in methanol are relatively high. Catalysts are often used to activate the bonds and to increase the selectivity to desired products.
Production
Methanol is prepared by pressure heating with carbon monoxide and hydrogen in the presence of a catalyst:
? ?
If the conditions are strictly controlled, the yield can reach 100% and the purity can reach 99%.
Methane is mixed with oxygen (9:1, V/V) and methanol is obtained through a copper tube under heating and pressure:
Toxicity evaluation
ADI is limited to GMP (FAO/WHO, 2001).
Toxic, can cause blindness.
LD50: 5628 mg/kg (rat, oral).
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Measurement
Date
System
Route/Organism
Dose
Effect
Skin and Eye Irritation
December 2016
?
eye /rabbit
40 mg
moderate
Skin and Eye Irritation
December 2016
?
eye /rabbit
100 mg/24H
moderate
Skin and Eye Irritation
December 2016
?
skin /rabbit
20 mg/24H
moderate
Mutation Data
December 2016
Cytogenetic Analysis
parenteral/grasshopper
3000 ppm
?
Mutation Data
December 2016
Cytogenetic Analysis
oral/mouse
1 gm/kg
?
Mutation Data
December 2016
Cytogenetic Analysis
intraperitoneal/mouse
75 mg/kg
?
Mutation Data
December 2016
DNA Damage
oral/rat
10 μmol/kg
?
Mutation Data
December 2016
DNA inhibition
lymphocyte/human
300 mmol/L
?
Mutation Data
December 2016
DNA repair
/Escherichia coli
20 mg/well
?
Mutation Data
December 2016
morphological transform
fibroblast/mouse
0.01 mg/L/21D (-enzymatic activation step)
?
from The National Institute for Occupational Safety and Health - NIOSH
Toxicity evaluation
The toxic properties of methanol are the result of accumulation
of the formate intermediate in the blood and tissues of exposed
individuals. Formate accumulation produces metabolic
acidosis leading to the characteristic ocular toxicity (blindness)
observed in human methanol poisonings.
Humans and primates appear particularly sensitive to
methanol toxicity when compared to rats. This is attributed to
the slower rate of conversion in humans of the formate
metabolite via tetrahydrofolate. This step in methanol metabolism
occurs in rats at a rate ～2.5 times that observed in
humans.
Formate appears to directly affect the retina and optic nerve
by acting as a mitochondrial toxin. It is believed that formate
acts as a metabolic poison by inhibiting cytochrome oxidase
activity. The cells of the optic nerve have low reserves of cytochrome
oxidase and thus may be particularly sensitive to
formate-induced metabolic inhibition.
Methanol gasoline
Methanol gasoline refers to the M series mixture fuel made of addition of methanol to the gasoline and formulated using methanol fuel solvent. Among them, M15 (add 15% methanol in gasoline) clean methanol gasoline is used as vehicle fuel, respectively, used in a variety of gasoline engines. It can be applied to substitute the finished gasoline without changing the existing engine structure, and can also be mixed with refined oil. The methanol mixed fuel has excellent thermal efficiency, power, start-up and being economical. It is also characterized by lowering the emissions, saving oil and being safe and convenient. Methanol gasoline types of M35, M15, M20, M50, N85 and M100 with different blend ratios have been developed around the world according to the conditions of different countries. At present, the commercial methanol is mainly M85 (85% methanol + 15% gasoline) and M100 with M100 performance being better than M85 and having greater environmental advantages.
History
It was first isolated in 1661 by the Irish chemist Robert Boyle
(1627–1691) who prepared it by the destructive distillation of boxwood, giving it the name
spirit of box, and the name wood alcohol is still used for methyl alcohol. Methyl alcohol is also
called pyroxylic spirit; pyroxylic is a general term meaning distilled from wood and indicates
that methyl alcohol is formed during pyrolysis of wood. The common name was derived in the
mid-1800s. The name methyl denotes the single carbon alkane methane in which a hydrogen
atom has been removed to give the methyl radical. The word alcohol is derived from Arabic
al kuhul.
Production Methods
Modern industrial-scale methanol production is exclusively
based on synthesis from pressurized mixtures of hydrogen,
carbon monoxide, and carbon dioxide gases in the presence
of catalysts. Based on production volume, methanol has
become one of the largest commodity chemicals produced
in the world.
Reactions
Methyl alcohol is a versatile material, reacting (1) with sodium metal, forming sodium methylate, sodium methoxide CH3ONa plus hydrogen gas, (2) with phosphorus chloride, bromide, iodide, forming methyl chloride, bromide, iodide, respectively, (3) with H2SO4 concentrated, forming dimethyl ether (CH3)2O, (4) with organic acids, warmed in the presence of H2SO4, forming esters, e.g., methyl acetate CH3COOCH3, [CAS: 79-20-9], methyl salicylate C6H4(OH)·COOCH3, possessing characteristic odors, (5) with magnesium methyl iodide in anhydrous ether (Grignard’s solution), forming methane as in the case of primary alcohols, (6) with calcium chloride, forming a solid addition compound 4CH3OH·CaCl2, which is decomposed by H2O, (7) with oxygen, in the presence of heated smooth copper or silver forming formaldehyde. The density of pure methyl alcohol is 0.792 at 20 °C compared with H2O at 4 °C (the corresponding figure for ethyl alcohol is 0.789), and the percentage of methyl alcohol present in a methyl alcohol-water solution may be determined from the density of the sample.
World Health Organization (WHO)
Methanol has been subjected to abuse by consumption as a
substitute for ethanol. Its toxic metabolites cause irreversible blindness and severe
metabolic acidosis, and are ultimately fatal. Methanol continues to be used as an
industrial solvent.
Reactivity Profile
Methanol reacts violently with acetyl bromide [Merck 11th ed. 1989]. Mixtures with concentrated sulfuric acid and concentrated hydrogen peroxide can cause explosions. Reacts with hypochlorous acid either in water solution or mixed water/carbon tetrachloride solution to give methyl hypochlorite, which decomposes in the cold and may explode on exposure to sunlight or heat. Gives the same product with chlorine. Can react explosively with isocyanates under basic conditions. The presence of an inert solvent mitigates this reaction [Wischmeyer 1969]. A violent exothermic reaction occurred between methyl alcohol and bromine in a mixing cylinder [MCA Case History 1863. 1972]. A flask of anhydrous lead perchlorate dissolved in Methanol exploded when Methanol was disturbed [J. Am. Chem. Soc. 52:2391. 1930]. P4O6 reacts violently with Methanol. (Thorpe, T. E. et al., J. Chem. Soc., 1890, 57, 569-573). Ethanol or Methanol can ignite on contact with a platinum-black catalyst. (Urben 1794).
Hazard
Flammable, dangerous fire risk. Explosive
limits in air 6–36.5% by volume. Toxic by ingestion
(causes blindness). Headache, eye damage, dizziness, and nausea.
Health Hazard
Ingestion of adulterated alcoholic beveragescontaining methanol has resulted in innumerable loss of human lives throughout theworld. It is highly toxic, causing acidosis andblindness. The symptoms of poisoning arenausea, abdominal pain, headache, blurredvision, shortness of breath, and dizziness.In the body, methanol oxidizes to formaldehyde and formic acid — the latter could bedetected in the urine, the pH of which is lowered (when poisoning is severe).The toxicity of methanol is attributed tothe metabolic products above. Ingestion inlarge amounts affects the brain, lungs, gastrointestinal tract, eyes, and respiratory system and can cause coma, blindness, anddeath. The lethal dose is reported to be60–250 mL. The poisoning effect is prolonged and the recovery is slow, often causing permanent loss of sight.Other exposure routes are inhalation andskin absorption. Exposure to methanol vaporto at 2000 ppm at regular intervals over aperiod of 4 weeks caused upper respiratorytract irritation and mucoid nasal discharge inrats. Such discharge was found to be a doserelated effect.Inhalation in humans may produce headache, drowsiness, and eye irritation. Prolonged skin contact may cause dermatitis andscaling. Eye contact can cause burns anddamage vision..
Health Hazard
The acute toxicity of methanol by ingestion, inhalation, and skin contact is low. Ingestion
of methanol or inhalation of high concentrations can produce headache, drowsiness,
blurred vision, nausea, vomiting, blindness, and death. In humans, 60 to 250 mL is
reported to be a lethal dose. Prolonged or repeated skin contact can cause irritation and
inflammation; methanol can be absorbed through the skin in toxic amounts. Contact of
methanol with the eyes can cause irritation and burns. Methanol is not considered to have
adequate warning properties.
Methanol has not been found to be carcinogenic in humans. Information available is
insufficient to characterize the reproductive hazard presented by methanol. In animal
tests, the compound produced developmental effects only at levels that were maternally
toxic; hence, it is not considered to be a highly significant hazard to the fetus. Tests in
bacterial or mammalian cell cultures demonstrate no mutagenic activity
Flammability and Explosibility
Methanol is a flammable liquid (NFPA rating = 3) that burns with an invisible flame
in daylight; its vapor can travel a considerable distance to an ignition source and
"flash back." Methanol-water mixtures will burn unless very dilute. Carbon dioxide
or dry chemical extinguishers should be used for methanol fires.
Chemical Reactivity
Reactivity with Water No reaction; Reactivity with Common Materials: No reaction; Stability During Transport: Stable; Neutralizing Agents for Acids and Caustics: Not pertinent; Polymerization:Not pertinent; Inhibitor of Polymerization: Not pertinent.
Safety Profile
A human poison by
ingestion. Poison experimentally by skin
contact. Moderately toxic experimentally by
intravenous and intraperitoneal routes.
Mildly toxic by inhalation. Human systemic
effects: changes in circulation, cough,
dyspnea, headache, lachrymation, nausea or
vomiting, optic nerve neuropathy,
respiratory effects, visual field changes. An
experimental teratogen. Experimental
reproductive effects. An eye and skin
irritant. Human mutation data reported. A
narcotic.
Its main toxic effect is exerted upon the
nervous system, particularly the optic nerves
and possibly the retinae. The condtion can
progress to permanent blindness. Once
absorbed, methanol is only very slowly
eliminated. Coma resulting from massive
exposures may last as long as 2-4 days. In
the body, the products formed by its
oxidation are formaldehyde and formic acid,
both of which are toxic. Because of the slow
elimination, methanol should be regarded as
a cumulative poison. Though single
exposures to fumes may cause no harmful
effect, daily exposure may result in the
accumulation of sufficient methanol in the
body to cause illness. Death from ingestion of less than 30 mL has been reported. A
common air contaminant.
Flammable liquid. Dangerous fire hazard
when exposed to heat, flame, or oxidlzers.
Explosive in the form of vapor when
exposed to heat or flame. Explosive reaction
with chloroform + sodium methoxide,
diethyl zinc. Violent reaction with alkyl
aluminum salts, acetyl bromide, chloroform
+ sodlum hydroxide, CrO3, cyanuric
chloride, (I + ethanol + HgO), Pb(ClO4)2,
HClO4, P2O3, (KOH + CHCb), nitric acid.
Incompatible with berylhum dihydride,
metals (e.g., potassium, magnesium),
oxidants (e.g., barium perchlorate, bromine,
sodium hypochlorite, chlorine, hydrogen
peroxide), potassium tert-butoxide, carbon
tetrachloride + metals (e.g., aluminum,
magnesium, zinc), dlchloromethane.
Dangerous; can react vigorously with
oxidizing materials. To fight fire, use alcohol
foam. When heated to decomposition it
emits acrid smoke and irritating fumes.
Source
Methanol occurs naturally in small-flowered oregano (5 to 45 ppm) (Baser et al., 1991),
Guveyoto shoots (700 ppb) (Baser et al., 1992), orange juice (0.8 to 80 ppm), onion bulbs,
pineapples, black currant, spearmint, apples, jimsonweed leaves, soybean plants, wild parsnip,
blackwood, soursop, cauliflower, caraway, petitgrain, bay leaves, tomatoes, parsley leaves, and
geraniums (Duke, 1992).
Methanol may enter the environment from methanol spills because it is used in formaldehyde
solutions to prevent polymerization (Worthing and Hance, 1991).
Environmental fate
Biological. In a 5-d experiment, [14C]methanol applied to soil water suspensions under aerobic
and anaerobic conditions gave 14CO2 yields of 53.4 and 46.3%, respectively (Scheunert et al.,
1987). Heukelekian and Rand (1955) reported a 5-d BOD value of 0.85 g/g which is 56.7% of the
ThOD value of 1.50 g/g. Using the BOD technique to measure biodegradation, the mean 5-d BOD
value (mM BOD/mM methanol) and ThOD were 0.93 and 62.0%, respectively (Vaishnav et al.,
1987).
Photolytic. Photooxidation of methanol in an oxygen-rich atmosphere (20%) in the presence of
chlorine atoms yielded formaldehyde and hydroxyperoxyl radicals. The reaction is initiated via
hydrogen abstraction by OH radicals or chlorine atoms yielding a hydroxymethyl radical.
Chlorine, formaldehyde, carbon monoxide, hydrogen peroxide, and formic acid were detected
(Whitbeck, 1983). Reported rate constants for the reaction of methanol and OH radicals in the
atmosphere: 5.7 x 10-11 cm3/mol·sec at 300 K (Hendry and Kenley, 1979), 5.7 x 10-8 L/mol·sec
(second-order) at 292 K (Campbell et al., 1976), 1.00 x 10-12 cm3/molecule·sec at 292 K (Meier et
al., 1985), 7.6 x 10-13 cm3/molecule·sec at 298 K (Ravishankara and Davis, 1978), 6.61 x 10-13
cm3/molecule·sec at room temperature (Wallington et al., 1988a). Based on an atmospheric OH
concentration of 1.0 x 106 molecule/cm3, the reported half-life of methanol is 8.6 d (Grosjean,
1997).
Chemical/Physical. In a smog chamber, methanol reacted with nitrogen dioxide to give methyl
nitrite and nitric acid (Takagi et al., 1986). The formation of these products was facilitated when
this experiment was accompanied by UV light (Akimoto and Takagi, 1986).
Methanol will not hydrolyze because it does not have a hydrolyzable functional group (Kollig,
1993).
At an influent concentration of 1,000 mg/L, treatment with GAC resulted in an effluent
concentration of 964 mg/L. The adsorbability of the carbon used was 7 mg/g carbon (Guisti et al.,
1974).
Hydroxyl radicals react with methanol in aqueous solution at a reaction rate of 1.60 x 10-12
cm3/molecule?sec (Wallington et al., 1988).
Complete combustion in air produces carbon dioxide and water. The stoichiometric equation for
this oxidation reaction is:
2CH4O + 3O2 → 2CO2 + 4H2O
storage
Methanol should
be used only in areas free of ignition sources, and quantities greater than 1 liter
should be stored in tightly sealed metal containers in areas separate from oxidizers.
Shipping
UN1230 Methanol, Hazard Class: 3; Labels:
3-Flammable liquid, 6.1-Poisonous material. (International)
Purification Methods
Almost all methanol is now obtained synthetically. Likely impurities are water, acetone, formaldehyde, ethanol, methyl formate and traces of dimethyl ether, methylal, methyl acetate, acetaldehyde, carbon dioxide and ammonia. Most of the water (down to about 0.01%) can be removed by fractional distillation. Drying with CaO is unnecessary and wasteful. Anhydrous methanol can be obtained from "absolute" material by passage through Linde type 4A molecular sieves, or by drying with CaH2, CaSO4, or with just a little more sodium than required to react with the water present, in all cases the methanol is then distilled. Two treatments with sodium reduces the water content to about 5 x 10-5%. [Friedman et al. J Am Chem Soc 83 4050 1961.] Lund and Bjerrum [Chem Ber 64 210 1931] warmed clean dry magnesium turnings (5g) and iodine (0.5g) with 50-75mL of "absolute" methanol in a flask until the iodine disappeared and all the magnesium was converted to the methoxide. Up to 1L of methanol was added and, after refluxing for 2-3hours, it was distilled off, excluding moisture from the system. Redistillation from tribromobenzoic acid removes basic impurities and traces of magnesium oxides, and leaves conductivity-quality material. The method of Hartley and Raikes [J Chem Soc 127 524 1925] gives a slightly better product. This consists of an initial fractional distillation, followed by distillation from aluminium methoxide, and then ammonia and other volatile impurities are removed by refluxing for 6hours with freshly dehydrated CuSO4 (2g/L) while dry air is passed through: the methanol is finally distilled. (The aluminium methoxide is prepared by warming with aluminium amalgam (3g/L) until all the aluminium has reacted. The amalgam is obtained by warming pieces of sheet aluminium with a solution of HgCl2 in dry methanol.) This treatment also removes aldehydes. If acetone is present in the methanol, it is usually removed prior to drying. Bates, Mullaly and Hartley [J Chem Soc 401 1923] dissolved 25g of iodine in 1L of methanol and then poured the solution, with constant stirring, into 500mL of M NaOH. Addition of 150mL of water precipitated iodoform. The solution was allowed to stand overnight, filtered, then boiled under reflux until the odour of iodoform disappeared, and fractionally distilled. (This treatment also removes formaldehyde.) Morton and Mark [Ind Eng Chem (Anal Edn) 6 151 1934] refluxed methanol (1L) with furfural (50mL) and 10% NaOH solution (120mL) for 6-12hours, the refluxing resin carries down with it the acetone and other carbonyl-containing impurities. The alcohol was then fractionally distilled. Evers and Knox [J Am Chem Soc 73 1739 1951], after refluxing 4.5L of methanol for 24hours with 50g of magnesium, distilled off 4L of it, which they then refluxed with AgNO3 for 24hours in the absence of moisture or CO2. The methanol was again distilled, shaken for 24hours with activated alumina before being filtered through a glass sinter and distilled under nitrogen in an all-glass still. Material suitable for conductivity work was obtained. Variations of the above methods have also been used. For example, a sodium hydroxide solution containing iodine has been added to methanol and, after standing for 1day, the solution has been poured slowly into about a quarter of its volume of 10% AgNO3, shaken for several hours, then distilled. Sulfanilic acid has been used instead of tribromobenzoic acid in Lund and Bjerrum's method. A solution of 15g of magnesium in 500mL of methanol has been heated under reflux, under nitrogen, with hydroquinone (30g), before degassing and distilling the methanol, which was subsequently stored with magnesium (2g) and hydroquinone (4g per 100mL). Refluxing for about 12hours removes the bulk of the formaldehyde from methanol: further purification has been obtained by subsequent distillation, refluxing for 12hours with dinitrophenylhydrazine (5g) and H2SO4 (2g/L), and again fractionally distilling. [Beilstein 1 IV 1227.]
Incompatibilities
Methanol reacts violently with strong
oxidizers, causing a fire and explosion hazard.
Waste Disposal
Consult with environmental
regulatory agencies for guidance on acceptable disposal
practices. Generators of waste containing this contaminant
(≥100 kg/mo) must conform to EPA regulations governing
storage, transportation, treatment, and waste disposal.
Incineration
Check Digit Verification of cas no
The CAS Registry Mumber 67-56-1 includes 5 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 2 digits, 6 and 7 respectively; the second part has 2 digits, 5 and 6 respectively.
Calculate Digit Verification of CAS Registry Number 67-56:
(4*6)+(3*7)+(2*5)+(1*6)=61
61 % 10 = 1
So 67-56-1 is a valid CAS Registry Number.
InChI:InChI=1/CH4O.H2O/c1-2;/h2H,1H3;1H2
67-56-1Relevant articles and documents
C-C Bond Cleavage of Acetonitrile by a Dinuclear Copper(II) Cryptate
Lu, Tongbu,Zhuang, Xiaomei,Li, Yanwu,Chen, Shi
, p. 4760 - 4761 (2004)
The dinuclear copper(II) cryptate [Cu2L](ClO4)4 (1) cleaves the C?C bond of acetonitrile at room temperature to produce a cyanide bridged complex of [Cu2L(CN)](ClO4)3·2CH3CN·4H2O (2). The cleavage mechanism is presented on the basis of the results of the crystal structure of 2, electronic absorption spectra, ESI-MS spectroscopy, and GC spectra of 1, respectively. Copyright
Photo-induced reduction of CO2 using a magnetically separable Ru-CoPc@TiO2@SiO2@Fe3O4 catalyst under visible light irradiation
Kumar, Pawan,Chauhan,Sain, Bir,Jain, Suman L.
, p. 4546 - 4553 (2015)
An efficient photo-induced reduction of CO2 using magnetically separable Ru-CoPc@TiO2@SiO2@Fe3O4 as a heterogeneous catalyst in which CoPc and Ru(bpy)2phene complexes were attached to a solid support via covalent attachment under visible light is described. The as-synthesized catalyst was characterized by a series of techniques including FTIR, UV-Vis, XRD, SEM, TEM, etc. and subsequently tested for the photocatalytic reduction of carbon dioxide using triethylamine as a sacrificial donor and water as a reaction medium. The developed photocatalyst exhibited a significantly higher catalytic activity to give a methanol yield of 2570.78 μmol per g cat after 48 h. This journal is
CO2 Reduction Promoted by Imidazole Supported on a Phosphonium-Type Ionic-Liquid-Modified Au Electrode at a Low Overpotential
Iijima, Go,Kitagawa, Tatsuya,Katayama, Akira,Inomata, Tomohiko,Yamaguchi, Hitoshi,Suzuki, Kazunori,Hirata, Kazuki,Hijikata, Yoshimasa,Ito, Miho,Masuda, Hideki
, p. 1990 - 2000 (2018)
The catalytic conversion of CO2 to useful compounds is of great importance from the viewpoint of global warming and development of alternatives to fossil fuels. Electrochemical reduction of CO2 using aromatic N-heterocylic molecules is a promising research area. We describe a high performance electrochemical system for reducing CO2 to formate, methanol, and CO using imidazole incorporated into a phosphonium-type ionic liquid-modified Au electrode, imidazole@IL/Au, at a low onset-potential of -0.32 V versus Ag/AgCl. This represents a significant improvement relative to the onset-potential obtained using a conventional Au electrode (-0.56 V). In the reduction carried out at -0.4 V, formate is mainly generated and methanol and CO are also generated with high efficiency at -0.6 ～ -0.8 V. The generation of methanol is confirmed by experiments using 13CO2 to generate 13CH3OH. To understand the reaction behavior of CO2 reduction, we characterized the reactions by conducting potential- and time-dependent in situ attenuated total reflection surface-enhanced infrared absorption spectroscopy (SEIRAS) measurements in D2O. During electrochemical CO2 reduction at -0.8 V, the C-O stretching band for CDOD (or COD) increases and the C=O stretching band for COOD increases at -0.4 V. These findings indicate that CO2 reduction intermediates, CDOD (or COD) and COOD, are formed, depending on the reduction potential, to convert CO2 to methanol and formate, respectively.
Photochemical and enzymatic synthesis of methanol from HCO3 - with dehydrogenases and zinc porphyrin
Amao, Yutaka,Watanabe, Tomoe
, p. 1544 - 1545 (2004)
Photochemical and enzymatic methanol synthesis from HCO3 - with formate dehydrogenase (FDH), aldehyde dehydrogenase (AldDH), and alcohol dehydrogenase (ADH) via the photoreduction of MV2+ using ZnTPPS photosensitization wa
Catalytic Activity of Nanosized CuO-ZnO Supported on Titanium Chips in Hydrogenation of Carbon Dioxide to Methyl Alcohol
Ahn, Ho-Geun,Lee, Hwan-Gyu,Chung, Min-Chul,Park, Kwon-Pil,Kim, Ki-Joong,Kang, Byeong-Mo,Jeong, Woon-Jo,Jung, Sang-Chul,Lee, Do-Jin
, p. 2024 - 2027 (2016)
In this study, titanium chips (TC) generated from industrial facilities was utilized as TiO2 support for hydrogenation of carbon dioxide (CO2) to methyl alcohol (CH3OH) over Cu-based catalysts. Nanosized CuO and ZnO catalysts were deposited on TiO2 support using a co-precipitation (CP) method (CuO-ZnO/TiO2), where the thermal treatment of TC and the particle size of TiO2 are optimized on CO2 conversion under different reaction temperature and contact time. Direct hydrogenation of CO2 to CH3OH over CuO-ZnO/TiO2 catalysts was achieved and the maximum selectivity (22%) and yield (18.2%) of CH3OH were obtained in the range of reaction temperature 210～240 °C under the 30 bar. The selectivity was readily increased by increasing the flow rate, which does not affect much to the CO2 conversion and CH3OH yield.
Photocatalytic conversion of carbon dioxide into methanol in reverse fuel cells with tungsten oxide and layered double hydroxide photocatalysts for solar fuel generation
Morikawa, Motoharu,Ogura, Yuta,Ahmed, Naveed,Kawamura, Shogo,Mikami, Gaku,Okamoto, Seiji,Izumi, Yasuo
, p. 1644 - 1651 (2014)
The phenomena of the photocatalytic oxidation of water and photocatalytic reduction of CO2 were combined using reverse photofuel cells, in which the two photocatalysts, WO3 and layered double hydroxide (LDH), were separated by a polymer electrolyte (PE) film. WO3 was used for the photooxidation of water, whereas LDH, comprising Zn, Cu, and Ga, was used for the photoreduction of CO2. For this process, photocatalysts pressed on both sides of the PE film were irradiated with UV-visible light through quartz windows and through the space in carbon electrode plates and water-repellent carbon paper for both gas flow and light transmission. 45% of the photocatalyst area was irradiated through the windows. The protons and electrons, which were formed on WO3 under the flow of helium and moisture, transferred to the LDH via the PE and external circuit, respectively. Methanol was the major product from the LDH under the flow of CO2 and helium. The observed photoreduction rates of CO2 to methanol accounted for 68%-100% of photocurrents. This supports the effectiveness of the combined photooxidation and photoreduction mechanism as a viable strategy to selectively produce methanol. In addition, we tested reverse photofuel cell-2, which consisted of a WO3 film pressed on C paper and LDH film pressed on Cu foil. The photoelectrodes were immersed in acidic solutions of pH 4, with the PE film distinguishing the two compartments. Both the photoelectrodes were completely irradiated by UV-visible light through the quartz windows. Consequently, the photocurrent from the LDH under CO2 flow to WO 3 under N2 flow was increased by 2.4-3.4 times in comparison to photofuel cell-1 tested under similar conditions. However, the major product from the LDH was H2 rather than methanol using photofuel cell-2. The photogenerated electrons in the irradiated area of the photocatalysts were obliged to diffuse laterally to the unirradiated area of photocatalysts in contact with the C papers in photofuel cell-1. This lateral diffusion reduced the photocatalytic conversion rates of CO2, despite the advantages of photofuel cell-1 in terms of selective formation and easy separation of gas-phase methanol. This journal is the Partner Organisations 2014.
Comparative Study of Diverse Copper Zeolites for the Conversion of Methane into Methanol
Park, Min Bum,Ahn, Sang Hyun,Mansouri, Ali,Ranocchiari, Marco,van Bokhoven, Jeroen A.
, p. 3705 - 3713 (2017)
The characterization and reactive properties of copper zeolites with twelve framework topologies (MOR, EON, MAZ, MEI, BPH, FAU, LTL, MFI, HEU, FER, SZR, and CHA) are compared in the stepwise partial oxidation of methane into methanol. Cu2+ ion-exchanged zeolite omega, a MAZ-type material, reveals the highest yield (86 μmol g(cat.)?1) among these materials after high-temperature activation and liquid methanol extraction. The high yield is ascribed to the relatively high density of copper–oxo active species, which form in its three-dimensional 8-membered (MB) ring channels. In situ UV/Vis studies show that diverse copper species form in different zeolites after high-temperature activation, suggesting that there are no universally active species. Nonetheless, there are some dominant factors required for achieving high methanol yields: 1) highly dispersed copper–oxo species; 2) large amount of exchanged copper in small-pore zeolites; 3) moderately high temperature of activation; and 4) use of proton form zeolite precursors. Cu-omega and Cu-mordenite, with the proton form of mordenite as the precursor, yield methanol after activation in oxygen and reaction with methane at only 200 °C, that is, under isothermal conditions.
Experimental measurements and kinetic modeling of CH4/O 2 and CH4/C2H6/02 conversion at high pressure
Rasmussen, Christian Lund,Geest Jakobsen,Glarborg, Peter
, p. 778 - 807 (2008)
A detailed chemical kinetic model for homogeneous combustion of the light hydrocarbon fuels CH4 and C2H6 in the intermediate temperature range roughly 500-1100 K, and pressures up to 100 bar has been developed and validated experimentally. Rate constants have been obtained from critical evaluation of data for individual elementary reactions reported in the literature with particular emphasis on the conditions relevant to the present work. The experiments, involving CH4/02 and CH4/C2H6/O2 mixtures diluted in N2 have been carried out in a high-pressure flow reactor at 600-900 K, 50-100 bar, and reaction stoichiometrics ranging from very lean to fuel-rich conditions. Model predictions are generally satisfactory. The governing reaction mechanisms are outlined based on calculations with the kinetic model. Finally, the mechanism was extended with a number of reactions important at high temperature and tested against data from shock tubes, laminar flames, and flow reactors.
Cobalt phthalocyanine immobilized on graphene oxide: An efficient visible-active catalyst for the photoreduction of carbon dioxide
Kumar, Pawan,Kumar, Arvind,Sreedhar, Bojja,Sain, Bir,Ray, Siddharth S.,Jain, Suman L.
, p. 6154 - 6161 (2014)
New graphene oxide (GO)-tethered-CoII phthalocyanine complex [CoPc-GO] was synthesized by a stepwise procedure and demonstrated to be an efficient, cost-effective and recyclable photocatalyst for the reduction of carbon dioxide to produce methanol as the main product. The developed GO-immobilized CoPc was characterized by X-ray diffraction (XRD), FTIR, XPS, Raman, diffusion reflection UV/Vis spectroscopy, inductively coupled plasma atomic emission spectroscopy (ICP-AES), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). FTIR, XPS, Raman, UV/Vis and ICP-AES along with elemental analysis data showed that CoII-Pc complex was successfully grafted on GO. The prepared catalyst was used for the photocatalytic reduction of carbon dioxide by using water as a solvent and triethylamine as the sacrificial donor. Methanol was obtained as the major reaction product along with the formation of minor amount of CO (0.82%). It was found that GO-grafted CoPc exhibited higher photocatalytic activity than homogeneous CoPc, as well as GO, and showed good recoverability without significant leaching during the reaction. Quantitative determination of methanol was done by GC flame-ionization detector (FID), and verification of product was done by NMR spectroscopy. The yield of methanol after 48 h of reaction by using GO-CoPc catalyst in the presence of sacrificial donor triethylamine was found to be 3781.8881 μmolg-1cat., and the conversion rate was found to be 78.7893 μmolg-1cat.h-1. After the photoreduction experiment, the catalyst was easily recovered by filtration and reused for the subsequent recycling experiment without significant change in the catalytic efficiency. Very photoactive! Cobalt phthalocyanine grafted to the chemically functionalized graphene oxide was found to be an efficient heterogeneous visible-light-induced photoredox catalyst for the photoreduction of carbon dioxide to methanol in a very good yield. The developed photocatalyst exhibited superior activity compared with the existing photocatalytic systems and gave methanol as the major reaction product (see scheme).
Facile synthesis of ZnO particles: Via benzene-assisted co-solvothermal method with different alcohols and its application
Maneechakr, Panya,Karnjanakom, Surachai,Samerjit, Jittima
, p. 73947 - 73952 (2016)
In this study, ZnO particles with different morphologies were synthesized by a novel co-solvothermal method using benzene. The prepared samples were characterized by Brunauer-Emmett-Teller (BET) measurements, X-ray diffractometry (XRD), scanning electron microscopy coupled with an energy dispersive X-ray detector (SEM-EDX), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectrometry (XPS), and H2-temperature programmed reduction (H2-TPR). The results showed that the molecular sizes and carbon numbers of the alcohols used in the reaction and the addition of benzene had a great effect on the morphologies, textural properties, and crystalline structures of the material products in our reaction system. Different ZnO morphologies, such as spherical coral-like, carnation-like, rose-like, and plate-like structures, were obtained using methanol, ethanol, propanol, and butanol, respectively. Moreover, Cu particles loaded on ZnO with different morphologies were also investigated for the hydrogenation of CO2 to CH3OH. High catalytic activity and selectivity (82.8%) for CH3OH formation were obtained using ZnO prepared from methanol with Cu doping (Cu/ZnO-Me).
